Usage patterns
〈場所〉に木の実がなるtree nuts/fruit grow (ripen) in a place
Lots of nuts and berries grow in this forest.
木の実を拾うto pick up fallen nuts or berries
The children played by picking up acorns and berries in the park.
〈動物〉が木の実を食べるan animal eats tree nuts/berries as food
Squirrels eat nuts to prepare for winter.
Expressions
木の実は本へ落つall returns to dust; the fruit of the tree falls to the roots